An Audio Input Under Linux Success Story, a Long Time in
Coming

Abstract

With a lot of hand holding, I was finally able to get my soundcard
to accept microphone input under Linux. Here's how.

Since I started using Linux seven years ago, I've never been able to
make a microphone work, although I've wanted to. I've never been able to
record sound or use any nifty applications that require audio input from me.
That is, until now. Here's how I got things to work, for my particular
little hardware corner-case. Like any other good Linux success story, this
one took a lot of hard work and patience to achieve.

The card with which I've been working is the one using the cs46xx
driver. To weave the magic, we'll be using alsamixer,
which I ran as root. You may want to use alsamixer -V all
in order to see all the options at once. For me, the trick was understanding
that there are three independent actions you can take on the various items
in this display. (I was previously only aware of two.) You can mute or unmute various items (with the "M" key), you
can change the volume on various items
(with the up and down arrows), and you can activate
capture on various items (with the space bar). It is this third
type of action that escaped me for so long.

Now plug in your microphone correctly, physically unmute that
microphone (if it has such a capability—many modern headsets do), and bring
up the alsamixer interface. These are the settings that were critical for
me.

Everything else unmuted, with the volume turned up (although I did
not do a thorough test of every other option)

Mad respef to
gnubien in #alsa on irc.freenode.net for being patient with me for
over two hours to get it working. I also found the
Alsa bugtracking
system useful for seeing what other people were trying (in my case,
report
1605).